Skip to content


Switch branches/tags

Name already in use

A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?

Latest commit


Git stats


Failed to load latest commit information.
Latest commit message
Commit time

TT-Toolbox (TT=Tensor Train) Version 2.2.2

TT(Tensor Train) format is an efficient way for low-parametric representation of high-dimensional tensors. The TT-Toolbox is a MATLAB implementation of basic operations with tensors in TT-format. It includes:

  • tt_tensor and tt_matrix classes for storing vectors and operators
  • Basic linear algebra subroutines (addition, matrix-by-vector product, elementwise multiplication and many others) using standard MATLAB syntax, linear complexity in the dimension, reshape function
  • Fast rounding procedure with a prescribed accuracy
  • Advanced approximation and solution techniques:
  • Approximate solution of linear systems and eigenvalue problems
  • Cross methods to approximate ``black-box'' tensors
  • Wavelet tensor train decomposition
  • Construction of basic operators and functions (Laplace operator, function of a TT-tensor)
  • Computation of maximal and minimal elements of a tensor
  • and several others

New in Version 2.2.2

  • one-element MATLAB-style subsref and subsassgn now possible for tt_matrix: current_value=ttm(123,4567) and ttm(123,4567)=new_value
  • submatrix extraction is now possible: ttm2=ttm([1 2 7],[1 2 1;1 1 2]) For additional help see code of @tt_matrix/subsref.m and core/tt_submatrix.m

New in Version 2.2.1

  • Blockwise assembly of tt_matrices added: ttM=tt_blockwise({ttA ttB ttC;ttD ttE ttF})
  • subtensor extraction is now possible: ttv2=ttv(1,2,:,2,2,:,:,:,1) or ttv2=ttv({1,2,':',2,2,':',':',':',1}) For additional help see code of @tt_tensor/subsref.m and core/tt_subtensor.m

New in Version 2.2

  • Better documentation
  • Mixed QTT-Tucker format (qtt_tucker class)
  • reshape function for a TT-tensor/TT-matrix
  • dmrg_cross method for black-box tensor approximation
  • Convolution in QTT-format